Two ultraviolet lamps light the same zinc plate in turn, equally bright, one higher in frequency than the other. Both eject electrons the instant they switch on. Under the higher-frequency lamp, the ejected electrons leave carrying more energy.
The last lesson raised the intensity and held the frequency, and more electrons came out each second. This lesson makes the opposite change: the frequency rises while the intensity stays fixed. What changes now is not the count.
Ejected electrons do not all leave with the same energy; some carry more than others.
The highest energy any one ejected electron carries is the maximum energy of the ejected electrons.
Swapping to a higher-frequency ultraviolet lamp on zinc, intensity unchanged, raises the maximum energy of the ejected electrons.
Intensity sets how many electrons leave each second; frequency sets the maximum energy an ejected electron can leave with.
A dim lamp of very high frequency ejects few electrons each second, with a high maximum energy.
A bright lamp just above the threshold ejects many electrons each second, with a low maximum energy.
In this topic, electron energies are compared, never calculated.
Violet light and green light both sit above cesium's threshold frequency. Lamps of equal intensity shine each color on a cesium plate in turn. Under which color do the ejected electrons reach a higher maximum energy?
Above the threshold, a higher frequency gives a higher maximum energy of the ejected electrons.
Violet light has a higher frequency than green light.
The intensities are equal, so only the frequency differs.
The electrons reach a higher maximum energy under the violet light.
An ultraviolet lamp on zinc is swapped for one of lower frequency, still above zinc's threshold, at the same intensity. What happens to the maximum energy of the ejected electrons?
Frequency sets the maximum energy of the ejected electrons.
The new lamp's frequency is lower, though still above the threshold.
A lower frequency means a lower maximum energy.
The maximum energy of the ejected electrons falls.
An ultraviolet lamp on zinc is swapped for a higher-frequency ultraviolet lamp of the same intensity. What happens to the maximum energy of the ejected electrons?
Una says: 'Raising the frequency of above-threshold light, at fixed intensity, is what raises the number of electrons ejected each second.' Is Una correct?
Zelda says: 'With the intensity fixed, raising the frequency of above-threshold light raises the maximum energy of the ejected electrons.' Is Zelda correct?
Blue light and violet light, at equal intensity, each eject electrons from a sodium plate in turn. Which statement is correct?
A lamp above a metal's threshold frequency is adjusted, and afterward the maximum energy of the ejected electrons is higher. Which adjustment does that?
Three lamps of equal intensity shine on a sodium plate in turn: a red lamp below sodium's threshold frequency, a blue lamp above it, and a violet lamp above it. Which lamp gives ejected electrons the highest maximum energy?